1. Field of the Invention
The present invention is directed to an apparatus for preserving still beverages. More particularly the present invention is directed to an apparatus for the preservation of wine through the removal of air from a previously opened bottle.
2. Description of the Prior Art
It is well known that wine spoils quickly when oxidized through exposure to air. In short, wine+air=vinegar. On the producer/supplier side, much time and money is spent in the quest for the ideal closure, one that seals and protects bottled wine from spoilage, while still allowing wine to benefit from bottle aging. Closures range from traditional cork, to synthetic materials, to screw caps. But on the retail/consumer side, the options for preserving wine, once opened, are few. If a bottle is not finished, it can be adequately maintained at room temperature for several hours—and usually no more than a day or two at most—before developing noticeable off flavors. Refrigeration may in some instances extend the useful life of an opened bottle, but again by now more than several days. The downside to refrigeration is that, when served below their optimal temperature, over-chilled wines often taste dead and lifeless.
One known method for the preservation of wine in a bottle is to evacuate the air space above the liquid once some of the wine has been consumed and then seal the bottle with a stopper. One system for accomplishing this is the Vac-U-Vin™ system. The Vac-U-Vin™ system requires a special stopper to be placed in the bottle neck. This stopper has a slit that acts as a non-return valve. The valve opens if a vacuum is created above the stopper to allow air to be sucked out of the bottle but closes again as soon as the external pressure is greater than the  pressure inside the bottle. To create a vacuum above the stopper, a manual suction pump is used. This operates satisfactorily, but pump operation is time-consuming and strenuous if an adequate level of vacuum is to be produced in the bottle. It has been observed that the maximum vacuum that can be achieved using the Vac-U-Vin™ pump is approximately 17 in-Hg. There is also no convenient or accurate method of determining when a suitable vacuum level has been achieved.
U.S. Pat. No. 4,684,033 describes another known method of preserving wine in an opened wine bottle by inflating a bladder inside the bottle to fill the space above the liquid and to prevent oxygen from reaching the wine. To do this is a time-consuming operation, which requires considerable manual dexterity in introducing a deflated bladder into the bottle and then inflating it. This method also requires that the bladder be removed, washed, and cleaned after each use.
Another option for preserving an opened bottle of wine involves pouring the contents of the opened bottled into a smaller bottle, decanter or the like having less airspace above the wine, inserting an airtight stopper and then storing. Finally, the air in an opened bottle may be replaced with a layer of inert gas, such as nitrogen, and stored. In one such system as described in U.S. Pat. No. 4,475,576, a stopper is inserted into a bottle to replace the cork and remain with the bottle for the lifetime of the wine. The stopper is provided with passageways and valves to permit the bottle to be pressed against a contact-operated dispenser head, directing a blast of inert gas such as Argon into the bottle to expel at first air, and subsequently a mixture of air and Argon or other inert gas, until the percentage of oxygen is so low as not to represent a threat to the wine.
On the commercial consumption side, however, none of these solutions are adequate. For instance, in restaurants, wine bars and the like where wine is served by the glass, the problem of  wine preservation is greatly magnified by the sheer number of bottles. Spoilage accounts for waste and lost profits when opened bottles of wine are not consumed before their useful shelf life. This often limits the selection of wines offered by the glass to those that are either (a) relatively inexpensive or (b) so popular that they are virtually guaranteed to be consumed shortly after opening (e.g. Chardonnay, Merlot, etc.). There is little incentive for expensive wines, older vintages, or lesser-known varietals to be offered where the chance of unfinished bottles and spoilage is great. It is impractical, particularly in a busy restaurant or bar, for servers to use any of the previously mentioned methods to preserve opened bottles of wine. Evacuating air from a bottle using a hand pump such as the Vac-U-Vin™ is time-consuming and inconsistent. A bartender is unlikely to take the time required to properly vacuum seal a bottle of wine by hand when there are customers waiting to be served. And if the pumping and sealing is delayed, the damage to the wine from exposure to air is already done.
Decanting and storing opened wine in smaller vessels is even more unrealistic in the commercial setting. And while inert gas systems find use in some retail serving establishments, such systems can be quite expensive due not in the least part to the continued consumption of the inert gas. Inert gas systems are also impractical due to their bulk and the space required to install and maintain such a system, in which each bottle of wine requires its own stopper and tap for dispensing the stored wine.
Mechanical pump systems located at the bar are expensive, slow, and noisy. One mechanical system is described in U.S. Pat. No. 5,215,129 and has been commercialized as “Le Verre de Vin” (the glass of wine) system. The system comprises a self-contained wall-mounted unit, which receives a wine bottle. Pressing the wine bottle into a housing and closing  electrical contacts housed therein starts a pump. Once the contacts are closed, the pump begins to draw air in the bottle through a stopper having a one-way valve.
While the Verre de Vin system can be used to evacuate air from a bottle of wine, it has some inherent operational—as well as commercial—drawbacks. Initially, because the system is designed without a vacuum tank, the pump must cycle on and off with each depression of the housing. This creates at least three interrelated problems. Initially, the pump is noisy and can be annoying to patrons of the establishment in which such a device is installed. Secondly, the pump can only be started and stopped a predetermined number of times over a set period. Any more frequent actuation can result in the failure of the motor. According to the specifications, the Verre de Vin system can evacuate no more than fifteen bottles over a five-minute period. In a busy bar setting, this number can easily be surpassed, resulting in partially consumed bottles being left un-evacuated. Third, because there is no storage tank to maintain a vacuum in the system, there is a delay between the actuation of the pump and the drawing of a vacuum on the bottle. This is a result of the pump having to also evacuate air from the line between the pump and the bottle. It has been observed that in order to achieve a vacuum of 22 in-Hg in a half-empty, standard 750 ml wine bottle using the Verre de Vin system requires 12 seconds. In a busy setting in which customers are waiting to be served, a bartender is unlikely to take this time to evacuate a bottle of wine between each pour, leading to partially-consumed bottles of wine being left exposed to air. Finally, due to the size and single-user nature of the Verre de Vin system, the owner of a bar or other establishment is forced to sacrifice precious bar space for mounting or housing the device in a central location accessible throughout the service area. These and other problems make the Verre de Vin system a less than ideal solution. 
Accordingly, there is a need for a simple, fast, low-cost system, capable of supporting multiple users, that can be easily implemented by restaurants and bars to enable such establishments to open a greater variety of wines for their “by the glass” consumers without fear of spoilage or suffering economic loss.